Overlapping code block groups for multiple codewords

ABSTRACT

Methods, systems, and devices for wireless communication are described that support overlapping code block groups (CBGs) for multiple codewords. A receiving device may receive multiple codewords from a transmitting device over a set of spatial layers. The receiving device may determine an association between a set of feedback bits and code blocks (CBs) of the multiple codewords. The association may be based on a CBG configuration, which may bundle one or more sets of CBs of the one or more codewords using time boundaries (e.g., symbols) or based on a uniform or proportional CB distribution. Based on whether decoding of the codewords is successful, the receiving device may transmit the set of feedback bits. The number of feedback bits may be the same regardless of whether one or two codewords are received.

CROSS REFERENCES

The present Application for Patent claims benefit of U.S. ProvisionalPatent Application No. 62/525,730 by Sun et al., entitled “OverlappingCode Block Groups for Multiple Codewords,” filed Jun. 27, 2017, assignedto the assignee hereof, and expressly incorporated by reference herein.

BACKGROUND

The following relates generally to wireless communication, and morespecifically to overlapping code block groups (CBGs) for multiplecodewords.

Wireless communications systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be capable ofsupporting communication with multiple users by sharing the availablesystem resources (e.g., time, frequency, and power). Examples of suchmultiple-access systems include code division multiple access (CDMA)systems, time division multiple access (TDMA) systems, frequencydivision multiple access (FDMA) systems, and orthogonal frequencydivision multiple access (OFDMA) systems (e.g., a Long Term Evolution(LTE) system, or a New Radio (NR) system). A wireless multiple-accesscommunications system may include a number of base stations or accessnetwork nodes, each simultaneously supporting communication for multiplecommunication devices, which may be otherwise known as user equipment(UE).

In some wireless communications systems, transport blocks (TBs) may beutilized for data transmissions. The TBs may be divided into smallercode blocks (CBs), which may be encoded with an error correcting code toadd redundancy. Exploitation of this redundancy in the encodedinformation may improve the reliability of the message by allowing areceiving device to correct for bit errors that may occur (e.g., due tonoise). Codewords may include a set of encoded CBs and each CB mayinclude information bits and additional bits for error detection (e.g.,cyclic redundancy check (CRC) bits, parity check bits, filler bits,etc.). A codeword may be transmitted over one or more spatial layershaving a given modulation and coding scheme (MCS). Groups of CBs (e.g.,of multiple codewords) may be transmitted concurrently or sequentiallyand when all of the CBs of a TB are received and decoded by thereceiving device, the receiving device may provide feedback informationto the transmitting device indicating whether the received TB has beensuccessfully decoded. However, the feedback information may not includean indication of which CBs or groups of CBs were unsuccessfully decoded,which may cause the transmitting device to retransmit the entire TB inresponse even when a portion of the CBs were successfully decoded. Moreefficient techniques for feedback are desired.

SUMMARY

The described techniques relate to improved methods, systems, devices,or apparatuses that support overlapping code block groups (CBGs) formultiple codewords. Generally, the described techniques provide for areceiving device to receive one or more codewords, each of whichincludes multiple code blocks (CBs). The one or more codewords may bereceived over a set of spatial layers. The receiving device maydetermine an association between a set of feedback bits (e.g.,acknowledgement (ACK) or negative ACK (NACK) feedback bits) and the CBsof the multiple codewords based on a CB or CBG configuration. Based onwhether decoding of the CBs that constitute a transport block (TB) issuccessful, the receiving device may transmit, to a transmitting device,a message that includes the set of feedback bits. In some cases, thenumber of feedback bits may be the same regardless of whether one or twocodewords are received and the CB or CBG configuration may bundle one ormore sets of CBs of the one or more codewords using time boundaries(e.g., symbols) or based on a uniform or proportional CB distribution.In response to the feedback bits, the transmitting device may determinewhich sets of CBs to retransmit.

A method of wireless communication is described. The method may includereceiving a transmission including a first codeword received over afirst set of layers and a second codeword received over a second set oflayers, the first codeword including a first plurality of CBs and thesecond codeword including a second plurality of CBs; performing adecoding operation on the first and second pluralities of CBs of thetransmission; determining an association between a set of feedback bitsfor the transmission and the first and second pluralities of CBs basedat least in part on a CBG configuration for the first and secondcodewords, where a number of bits of the set of feedback bits correspondto a number of CBs for a single layer transmission; and transmitting amessage including the set of feedback bits based at least in part on aresult of the decoding operation and the determined association.

An apparatus for wireless communication is described. The apparatus mayinclude means for receiving a transmission including a first codewordreceived over a first set of layers and a second codeword received overa second set of layers, the first codeword including a first pluralityof CBs and the second codeword including a second plurality of CBs;means for performing a decoding operation on the first and secondpluralities of CBs of the transmission; means for determining anassociation between a set of feedback bits for the transmission and thefirst and second pluralities of CBs based at least in part on a CBGconfiguration for the first and second codewords, where a number of bitsof the set of feedback bits correspond to a number of CBs for a singlelayer transmission; and means for transmitting a message including theset of feedback bits based at least in part on a result of the decodingoperation and the determined association.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to receive a transmission including afirst codeword received over a first set of layers and a second codewordreceived over a second set of layers, the first codeword including afirst plurality of CBs and the second codeword including a secondplurality of CBs; perform a decoding operation on the first and secondpluralities of CBs of the transmission; determine an association betweena set of feedback bits for the transmission and the first and secondpluralities of CBs based at least in part on a CBG configuration for thefirst and second codewords, where a number of bits of the set offeedback bits correspond to a number of CBs for a single layertransmission; and transmit a message including the set of feedback bitsbased at least in part on a result of the decoding operation and thedetermined association.

A non-transitory computer readable medium for wireless communication isdescribed. The non-transitory computer-readable medium may includeinstructions operable to cause a processor to receive a transmissionincluding a first codeword received over a first set of layers and asecond codeword received over a second set of layers, the first codewordincluding a first plurality of CBs and the second codeword including asecond plurality of CBs; perform a decoding operation on the first andsecond pluralities of CBs of the transmission; determine an associationbetween a set of feedback bits for the transmission and the first andsecond pluralities of CBs based at least in part on a CBG configurationfor the first and second codewords, where a number of bits of the set offeedback bits correspond to a number of CBs for a single layertransmission; and transmit a message including the set of feedback bitsbased at least in part on a result of the decoding operation and thedetermined association.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the CBG configurationincludes: assigning the first and second pluralities of CBs to CBGsaccording to time resource boundaries for the first and secondcodewords.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, determining the associationbetween the set of feedback bits and the first and second pluralities ofCBs includes bundling respective CBGs of the first and second codewords.Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for associating each feedback bit ofthe set of feedback bits with a respective bundled CBG.

Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for determining the number of feedbackbits based at least in part on a number of symbols of the set ofsymbols, where each CBG of the CBGs spans a symbol of the set ofsymbols.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, determining the associationbetween the set of feedback bits and the first and second pluralities ofCBs includes determining a number of CBG bundles based at least in parton the number of bits of the set of feedback bits. Some examples of themethod, apparatus, and non-transitory computer-readable medium describedabove may further include processes, features, means, or instructionsfor splitting the number of CBG bundles into a first set of CBG bundlesfor the first codeword and a second set of CBG bundles for the secondcodeword. Some examples of the method, apparatus, and non-transitorycomputer-readable medium described above may further include processes,features, means, or instructions for bundling consecutive CBGs of thefirst codeword and the second codeword into the first and second sets ofCBG bundles.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the number of CBG bundles maybe uniformly split into the first set of CBG bundles and the second setof CBG bundles.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the number of CBG bundles maybe split into the first set of CBG bundles and the second set of CBGbundles in proportion to a number of CBs in the first codeword and anumber of CBs in the second codeword.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the message includes afeedback application bitmap indicating the applicability of the set offeedback bits to one or both of the first codeword or to the secondcodeword.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the feedback applicationbitmap indicates whether all CBGs of one or both of the first codewordor the second codeword failed the decoding operation.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, a number of CBs of the firstplurality of CBs may be different from a number of CBs of the secondplurality of CBs.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the CBG configurationincludes: assigning the first and second pluralities of CBs to CBGsaccording to a uniform distribution.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, determining the associationbetween the feedback bits and the first and second pluralities of CBsincludes determining a number of CBGs based at least in part on thenumber of bits of the set of feedback bits. Some examples of the method,apparatus, and non-transitory computer-readable medium described abovemay further include processes, features, means, or instructions forsplitting the number of CBGs into a first set of CBGs for the firstcodeword and a second set of CBGs for the second codeword in proportionto a number of CBs in the first codeword and a number of CBs in thesecond codeword. Some examples of the method, apparatus, andnon-transitory computer-readable medium described above may furtherinclude processes, features, means, or instructions for uniformlysplitting the first plurality of CBs into the first set of CBGs and thesecond plurality of CBs into the second set of CBGs.

A method of wireless communication is described. The method may includetransmitting, in a first transmission, a first codeword over a first setof layers and a second codeword over a second set of layers, the firstcodeword including a first plurality of CBs and the second codewordincluding a second plurality of CBs; receiving a message including a setof feedback bits for the first codeword and the second codeword, the setof feedback bits associated with the first and second pluralities of CBsbased at least in part on a CBG configuration for the first and secondcodewords, where a number of bits of the set of feedback bits correspondto a number of CBs for a single layer transmission; and determiningwhether to retransmit a CB of the first or second pluralities of CBsbased at least in part on the set of feedback bits.

An apparatus for wireless communication is described. The apparatus mayinclude means for transmitting, in a first transmission, a firstcodeword over a first set of layers and a second codeword over a secondset of layers, the first codeword including a first plurality of CBs andthe second codeword including a second plurality of CBs; means forreceiving a message including a set of feedback bits for the firstcodeword and the second codeword, the set of feedback bits associatedwith the first and second pluralities of CBs based at least in part on aCBG configuration for the first and second codewords, where a number ofbits of the set of feedback bits correspond to a number of CBs for asingle layer transmission; and means for determining whether toretransmit a CB of the first or second pluralities of CBs based at leastin part on the set of feedback bits.

Another apparatus for wireless communication is described. The apparatusmay include a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe operable to cause the processor to transmit, in a first transmission,a first codeword over a first set of layers and a second codeword over asecond set of layers, the first codeword including a first plurality ofCBs and the second codeword including a second plurality of CBs; receivea message including a set of feedback bits for the first codeword andthe second codeword, the set of feedback bits associated with the firstand second pluralities of CBs based at least in part on a CBGconfiguration for the first and second codewords, where a number of bitsof the set of feedback bits correspond to a number of CBs for a singlelayer transmission; and determine whether to retransmit a CB of thefirst or second pluralities of CBs based at least in part on the set offeedback bits.

A non-transitory computer readable medium for wireless communication isdescribed. The non-transitory computer-readable medium may includeinstructions operable to cause a processor to transmit, in a firsttransmission, a first codeword over a first set of layers and a secondcodeword over a second set of layers, the first codeword including afirst plurality of CBs and the second codeword including a secondplurality of CBs; receive a message including a set of feedback bits forthe first codeword and the second codeword, the set of feedback bitsassociated with the first and second pluralities of CBs based at leastin part on a CBG configuration for the first and second codewords, wherea number of bits of the set of feedback bits correspond to a number ofCBs for a single layer transmission; and determine whether to retransmita CB of the first or second pluralities of CBs based at least in part onthe set of feedback bits.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the CBG configuration includesassigning the first and second pluralities of CBs to CBGs according totime resource boundaries for the first and second codewords.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, determining whether toretransmit the CB includes: bundling respective CBGs of the first andsecond codewords. Some examples of the method, apparatus, andnon-transitory computer-readable medium described above may furtherinclude processes, features, means, or instructions for associating eachfeedback bit of the set of feedback bits with a respective bundled CBG.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, each CBG of the CBGs spans asymbol of a set of symbols over which the first transmission may betransmitted.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, determining whether toretransmit the CB includes determining a number of CBG bundles based atleast in part on the number of bits of the set of feedback bits. Someexamples of the method, apparatus, and non-transitory computer-readablemedium described above may further include processes, features, means,or instructions for splitting the number of CBG bundles into a first setof CBG bundles for the first codeword and a second set of CBG bundlesfor the second codeword. Some examples of the method, apparatus, andnon-transitory computer-readable medium described above may furtherinclude processes, features, means, or instructions for bundlingconsecutive CBGs of the first codeword and the second codeword into thefirst and second sets of CBG bundles.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the number of CBG bundles maybe uniformly split into the first set of CBG bundles and the second setof CBG bundles.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the number of CBG bundles maybe split into the first set of CBG bundles and the second set of CBGbundles in proportion to a number of CBs in the first codeword and anumber of CBs in the second codeword.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the message includes afeedback application bitmap indicating the applicability of the set offeedback bits to one or both of the first codeword or to the secondcodeword.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the feedback applicationbitmap indicates whether all CBGs of one or both of the first codewordor the second codeword failed the decoding operation.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, a number of CBs of the firstplurality of CBs may be different from a number of CBs of the secondplurality of CBs.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, the CBG configurationincludes: assigning the first and second pluralities of CBs to CBGsaccording to a uniform distribution.

In some examples of the method, apparatus, and non-transitorycomputer-readable medium described above, determining whether toretransmit the CB includes: determining a number of CBGs based at leastin part on the number of bits of the set of feedback bits. Some examplesof the method, apparatus, and non-transitory computer-readable mediumdescribed above may further include processes, features, means, orinstructions for splitting the number of CBGs into a first set of CBGsfor the first codeword and a second set of CBGs for the second codewordin proportion to a number of CBs in the first codeword and a number ofCBs in the second codeword. Some examples of the method, apparatus, andnon-transitory computer-readable medium described above may furtherinclude processes, features, means, or instructions for uniformlysplitting the first plurality of CBs into the first set of CBGs and thesecond plurality of CBs into the second set of CBGs.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a system for wireless communicationthat supports overlapping code block groups (CBGs) for multiplecodewords in accordance with aspects of the present disclosure.

FIG. 2 illustrates an example of a wireless communications system thatsupports overlapping CBGs for multiple codewords in accordance withaspects of the present disclosure.

FIG. 3 illustrates an example of a codeword that supports overlappingCBGs for multiple codewords in accordance with aspects of the presentdisclosure.

FIG. 4 illustrates an example of a CBG configuration that supportsoverlapping CBGs for multiple codewords in accordance with aspects ofthe present disclosure.

FIG. 5 illustrates an example of codeword configurations that supportoverlapping CBGs for multiple codewords in accordance with aspects ofthe present disclosure.

FIG. 6 illustrates an example of CBG configurations that supportoverlapping CBGs for multiple codewords in accordance with aspects ofthe present disclosure.

FIGS. 7 through 9 show block diagrams of a device that supportsoverlapping code block groups for multiple codewords in accordance withaspects of the present disclosure.

FIG. 10 illustrates a block diagram of a system including a wirelessdevice that supports overlapping code block groups for multiplecodewords in accordance with aspects of the present disclosure.

FIGS. 11 and 12 illustrate methods for overlapping code block groups formultiple codewords in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

The described techniques relate to improved methods, systems, devices,or apparatuses that support overlapping code block groups (CBGs) formultiple codewords. A transport block (TB) may be utilized for datatransmissions. The TBs may be divided into smaller code blocks (CBs) anda codeword may be generated that includes a set of encoded CBs. Each CBmay include additional bits that may be used for error detection andcorrection. A CBG may include a set of CBs from one or more TBs and,after decoding a set of CBs corresponding to a TB, a receiving devicemay send feedback to the transmitting device to indicate whetherdecoding of the TB was successful. For example, when one or more of theCBs is not successfully decoded by a receiving device, the receivingdevice may transmit a negative acknowledgement (NACK) indicating thecorresponding CBG with unsuccessfully transmitted CB(s); alternativelyor additionally, an acknowledgement (ACK) may be transmitted to indicatethat a corresponding CBG has been successfully decoded. In some cases,an ACK/NACK feedback bit may be reserved for each CBG of the codeword. Atransmitting device (e.g., a base station) may retransmit the CBs withineach CBG for which a NACK has been received. The retransmission may beperformed using a hybrid automatic repeat request (HARQ) process, ratherthan retransmitting the entire TB.

In some cases, multiple codewords (e.g., two) may be transmitted when acertain number of spatial layers are utilized for uplink and/or downlinktransmissions. However, even when multiple codewords are transmitted,the number of ACK/NACK feedback bits may be limited to the number offeedback bits used for transmission of a single codeword. In someexamples, a transmitting device may group the CBGs of both codewordstogether in a certain format in order to ensure that all CBs have an atleast partly associated ACK/NACK feedback bit while leaving the totalnumber of ACK/NACK feedback bits static. In some examples, the first andsecond codewords may have corresponding CBGs (e.g., each defined by thesame boundaries) and corresponding CBGs may be bundled for associationwith the ACK/NACK feedback bits. In other examples, CBGs of eachcodeword may be bundled together uniformly for association with theACK/NACK feedback bits such that approximately the same number of CBGsare bundled together, uniformly or non-uniformly (e.g., in proportion tonumber of CBs). As used herein, the term “uniformly” should beunderstood to include approximately uniformly based on splitting aninteger into groups of integers. For example, uniformly may mean thatany given CBG bundle has at most one more CBG than any other CBG bundle.That is, a number N of CBGs may be uniformly bundled if there are X CBGbundles with R CBGs and Y bundles with S CBGs such that X*R+Y*S=N. Theremay be a variety of ways to uniformly group CBGs. In other examples, thenumber of CBs may be split among a number of CBGs for both (or multiple)codewords based on the total number of CBs between both codewords. Inother examples, additional bits may be added to the ACK/NACK feedbackbits to provide a bitmap to indicate for which codewords (i.e., thefirst codeword, the second codeword, or both) the ACK/NACK feedback bitsare intended.

Aspects of the disclosure are initially described in the context of awireless communications system. Various codeword and CBG configurationsare then described. A process flow illustrating aspects of thedisclosure is also described. Aspects of the disclosure are furtherillustrated by and described with reference to apparatus diagrams,system diagrams, and flowcharts that relate to overlapping CBGs formultiple codewords.

FIG. 1 illustrates an example of a wireless communications system 100 inaccordance with various aspects of the present disclosure. The wirelesscommunications system 100 includes base stations 105, UEs 115, and acore network 130. In some examples, the wireless communications system100 may be a Long Term Evolution (LTE) network, LTE-Advanced (LTE-A)network, or a New Radio (NR) network. In some cases, wirelesscommunications system 100 may support enhanced broadband communications,ultra-reliable (i.e., mission critical) communications, low latencycommunications, and communications with low-cost and low-complexitydevices.

Base stations 105 may wirelessly communicate with UEs 115 via one ormore base station antennas. Each base station 105 may providecommunication coverage for a respective geographic coverage area 110.Communication links 125 shown in wireless communications system 100 mayinclude uplink transmissions from a UE 115 to a base station 105, ordownlink transmissions, from a base station 105 to a UE 115. Controlinformation and data may be multiplexed on an uplink channel or downlinkaccording to various techniques. Control information and data may bemultiplexed on a downlink channel, for example, using time divisionmultiplexing (TDM) techniques, frequency division multiplexing (FDM)techniques, or hybrid TDM-FDM techniques. In some examples, the controlinformation transmitted during a transmission time interval (TTI) of adownlink channel may be distributed between different control regions ina cascaded manner (e.g., between a common control region and one or moreUE-specific control regions).

UEs 115 may be dispersed throughout the wireless communications system100, and each UE 115 may be stationary or mobile. A UE 115 may also bereferred to as a mobile station, a subscriber station, a mobile unit, asubscriber unit, a wireless unit, a remote unit, a mobile device, awireless device, a wireless communications device, a remote device, amobile subscriber station, an access terminal, a mobile terminal, awireless terminal, a remote terminal, a handset, a user agent, a mobileclient, a client, or some other suitable terminology. A UE 115 may be acellular phone, a personal digital assistant (PDA), a wireless modem, awireless communication device, a handheld device, a tablet computer, alaptop computer, a cordless phone, a personal electronic device, ahandheld device, a personal computer, a wireless local loop (WLL)station, an Internet of Things (IoT) device, an Internet of Everything(IoE) device, a machine type communication (MTC) device, an appliance,an automobile, or the like.

In some cases, a UE 115 may also be able to communicate directly withother UEs (e.g., using a peer-to-peer (P2P) or device-to-device (D2D)protocol). One or more of a group of UEs 115 utilizing D2Dcommunications may be within the coverage area 110 of a cell. Other UEs115 in such a group may be outside the coverage area 110 of a cell, orotherwise unable to receive transmissions from a base station 105. Insome cases, groups of UEs 115 communicating via D2D communications mayutilize a one-to-many (1:M) system in which each UE 115 transmits toevery other UE 115 in the group. In some cases, a base station 105facilitates the scheduling of resources for D2D communications. In othercases, D2D communications are carried out independent of a base station105.

Some UEs 115, such as MTC or IoT devices, may be low cost or lowcomplexity devices, and may provide for automated communication betweenmachines, i.e., Machine-to-Machine (M2M) communication. M2M or MTC mayrefer to data communication technologies that allow devices tocommunicate with one another or a base station without humanintervention. For example, M2M or MTC may refer to communications fromdevices that integrate sensors or meters to measure or captureinformation and relay that information to a central server orapplication program that can make use of the information or present theinformation to humans interacting with the program or application. SomeUEs 115 may be designed to collect information or enable automatedbehavior of machines. Some examples of applications for MTC devicesinclude smart metering, inventory monitoring, water level monitoring,equipment monitoring, healthcare monitoring, wildlife monitoring,weather and geological event monitoring, fleet management and tracking,remote security sensing, physical access control, and transaction-basedbusiness charging.

In some cases, an MTC device may operate using half-duplex (one-way)communications at a reduced peak rate. MTC devices may also beconfigured to enter a power saving “deep sleep” mode when not engagingin active communications. In some cases, MTC or IoT devices may bedesigned to support mission critical functions and wirelesscommunications system may be configured to provide ultra-reliablecommunications for these functions.

Base stations 105 may communicate with the core network 130 and with oneanother. For example, base stations 105 may interface with the corenetwork 130 through backhaul links 132 (e.g., S1, etc.). Base stations105 may communicate with one another over backhaul links 134 (e.g., X2,etc.) either directly or indirectly (e.g., through core network 130).Base stations 105 may perform radio configuration and scheduling forcommunication with UEs 115, or may operate under the control of a basestation controller (not shown). In some examples, base stations 105 maybe macro cells, small cells, hot spots, or the like. Base stations 105may also be referred to as evolved NodeBs (eNBs) 105.

A base station 105 may be connected by an S1 interface to the corenetwork 130. The core network may be an evolved packet core (EPC), whichmay include at least one mobility management entity (MME), at least oneserving gateway (S-GW), and at least one Packet Data Network (PDN)gateway (P-GW). The MME may be the control node that processes thesignaling between the UE 115 and the EPC. All user Internet Protocol(IP) packets may be transferred through the S-GW, which itself may beconnected to the P-GW. The P-GW may provide IP address allocation aswell as other functions. The P-GW may be connected to the networkoperators IP services. The operators IP services may include theInternet, the Intranet, an IP Multimedia Subsystem (IMS), and aPacket-Switched (PS) Streaming Service.

The core network 130 may provide user authentication, accessauthorization, tracking, Internet Protocol (IP) connectivity, and otheraccess, routing, or mobility functions. At least some of the networkdevices may include subcomponents such as an access network entity,which may be an example of an access node controller (ANC). Each accessnetwork entity may communicate with a number of UEs 115 through a numberof other access network transmission entities, each of which may be anexample of a smart radio head, or a transmission/reception point (TRP).In some configurations, various functions of each access network entityor base station 105 may be distributed across various network devices(e.g., radio heads and access network controllers) or consolidated intoa single network device (e.g., a base station 105).

Wireless communications system 100 may operate in an ultra-highfrequency (UHF) frequency region using frequency bands from 700 MHz to2600 MHz (2.6 GHz), although some networks (e.g., a wireless local areanetwork (WLAN)) may use frequencies as high as 4 GHz. This region mayalso be known as the decimeter band, since the wavelengths range fromapproximately one decimeter to one meter in length. UHF waves maypropagate mainly by line of sight, and may be blocked by buildings andenvironmental features. However, the waves may penetrate wallssufficiently to provide service to UEs 115 located indoors. Transmissionof UHF waves is characterized by smaller antennas and shorter range(e.g., less than 100 km) compared to transmission using the smallerfrequencies (and longer waves) of the high frequency (HF) or very highfrequency (VHF) portion of the spectrum. In some cases, wirelesscommunications system 100 may also utilize extremely high frequency(EHF) portions of the spectrum (e.g., from 30 GHz to 300 GHz). Thisregion may also be known as the millimeter band, since the wavelengthsrange from approximately one millimeter to one centimeter in length.Thus, EHF antennas may be even smaller and more closely spaced than UHFantennas. In some cases, this may facilitate use of antenna arrayswithin a UE 115 (e.g., for directional beamforming). However, EHFtransmissions may be subject to even greater atmospheric attenuation andshorter range than UHF transmissions.

Thus, wireless communications system 100 may support millimeter wave(mmW) communications between UEs 115 and base stations 105. Devicesoperating in mmW or EHF bands may have multiple antennas to allowbeamforming. That is, a base station 105 may use multiple antennas orantenna arrays to conduct beamforming operations for directionalcommunications with a UE 115. Beamforming (which may also be referred toas spatial filtering or directional transmission) is a signal processingtechnique that may be used at a transmitter (e.g., a base station 105)to shape and/or steer an overall antenna beam in the direction of atarget receiver (e.g., a UE 115). This may be achieved by combiningelements in an antenna array in such a way that transmitted signals atparticular angles experience constructive interference while othersexperience destructive interference.

Multiple-input multiple-output (MIMO) wireless systems use atransmission scheme between a transmitter (e.g., a base station 105) anda receiver (e.g., a UE 115), where both transmitter and receiver areequipped with multiple antennas. Some portions of wirelesscommunications system 100 may use beamforming. For example, base station105 may have an antenna array with a number of rows and columns ofantenna ports that the base station 105 may use for beamforming in itscommunication with UE 115. Signals may be transmitted multiple times indifferent directions (e.g., each transmission may be beamformeddifferently). A mmW receiver (e.g., a UE 115) may try multiple beams(e.g., antenna subarrays) while receiving the synchronization signals.

In some cases, the antennas of a base station 105 or UE 115 may belocated within one or more antenna arrays, which may support beamformingor MIMO operation. One or more base station antennas or antenna arraysmay be collocated at an antenna assembly, such as an antenna tower. Insome cases, antennas or antenna arrays associated with a base station105 may be located in diverse geographic locations. A base station 105may multiple use antennas or antenna arrays to conduct beamformingoperations for directional communications with a UE 115.

In some cases, wireless communications system 100 may be a packet-basednetwork that operate according to a layered protocol stack. In the userplane, communications at the bearer or Packet Data Convergence Protocol(PDCP) layer may be IP-based. A Radio Link Control (RLC) layer may insome cases perform packet segmentation and reassembly to communicateover logical channels. A Medium Access Control (MAC) layer may performpriority handling and multiplexing of logical channels into transportchannels. The MAC layer may also use HARQ to provide retransmission atthe MAC layer to improve link efficiency. In the control plane, theRadio Resource Control (RRC) protocol layer may provide establishment,configuration, and maintenance of an RRC connection between a UE 115 anda network device (e.g., a base station 105 or node of the core network130) supporting radio bearers for user plane data. At the Physical (PHY)layer, transport channels may be mapped to physical channels.

Time intervals in LTE or NR may be expressed in multiples of a basictime unit (which may be a sampling period of T_(s)=1/30,720,000seconds). Time resources may be organized according to radio frames oflength of 10 ms (T_(f)=307200T_(s)), which may be identified by a systemframe number (SFN) ranging from 0 to 1023. Each frame may include ten 1ms subframes numbered from 0 to 9. A subframe may be further dividedinto two 0.5 ms slots, each of which contains 6 or 7 modulation symbolperiods (depending on the length of the cyclic prefix prepended to eachsymbol). Excluding the cyclic prefix, each symbol contains 2048 sampleperiods. In some cases the subframe may be the smallest scheduling unit,also known as a TTI. In other cases, a TTI may be shorter than asubframe or may be dynamically selected (e.g., in short TTI bursts or inselected component carriers using short TTIs).

A resource element may consist of one symbol period and one subcarrier(e.g., a 15 KHz frequency range). A resource block may contain 12consecutive subcarriers in the frequency domain and, for a normal cyclicprefix in each Orthogonal Frequency Division Multiplexing (OFDM) symbol,7 consecutive OFDM symbols in the time domain (1 slot), or 84 resourceelements. The number of bits carried by each resource element may dependon the modulation scheme (the configuration of symbols that may beselected during each symbol period). Thus, the more resource blocks thata UE receives and the higher the modulation scheme, the higher the datarate may be.

Wireless communications system 100 may support operation on multiplecells or carriers, a feature which may be referred to as carrieraggregation (CA) or multi-carrier operation. A carrier may also bereferred to as a component carrier (CC), a layer, a channel, etc. Theterms “carrier,” “component carrier,” “cell,” and “channel” may be usedinterchangeably herein. A UE 115 may be configured with multipledownlink CCs and one or more uplink CCs for carrier aggregation. Carrieraggregation may be used with both Frequency Division Duplexing (FDD) andTime Division Duplexing (TDD) component carriers.

In some cases, wireless communications system 100 may utilize enhancedcomponent carriers (eCCs). An eCC may be characterized by one or morefeatures including: wider bandwidth, shorter symbol duration, shorterTTIs, and modified control channel configuration. In some cases, an eCCmay be associated with a carrier aggregation configuration or a dualconnectivity configuration (e.g., when multiple serving cells have asuboptimal or non-ideal backhaul link). An eCC may also be configuredfor use in unlicensed spectrum or shared spectrum (where more than oneoperator is allowed to use the spectrum). An eCC characterized by widebandwidth may include one or more segments that may be utilized by UEs115 that are not capable of monitoring the whole bandwidth or prefer touse a limited bandwidth (e.g., to conserve power).

In some cases, an eCC may utilize a different symbol duration than otherCCs, which may include use of a reduced symbol duration as compared withsymbol durations of the other CCs. A shorter symbol duration isassociated with increased subcarrier spacing. A device, such as a UE 115or base station 105, utilizing eCCs may transmit wideband signals (e.g.,20, 40, 60, 80 MHz, etc.) at reduced symbol durations (e.g., 16.67microseconds). A TTI in eCC may consist of one or multiple symbols. Insome cases, the TTI duration (that is, the number of symbols in a TTI)may be variable.

A shared radio frequency spectrum band may be utilized in an NR sharedspectrum system. For example, an NR shared spectrum may utilize anycombination of licensed, shared, and unlicensed spectrums, among others.The flexibility of eCC symbol duration and subcarrier spacing may allowfor the use of eCC across multiple spectrums. In some examples, NRshared spectrum may increase spectrum utilization and spectralefficiency, specifically through dynamic vertical (e.g., acrossfrequency) and horizontal (e.g., across time) sharing of resources.

In some cases, wireless communications system 100 may utilize bothlicensed and unlicensed radio frequency spectrum bands. For example,wireless communications system 100 may employ LTE License AssistedAccess (LTE-LAA) or LTE Unlicensed (LTE U) radio access technology or NRtechnology in an unlicensed band such as the 5 GHz Industrial,Scientific, and Medical (ISM) band. When operating in unlicensed radiofrequency spectrum bands, wireless devices such as base stations 105 andUEs 115 may employ listen-before-talk (LBT) procedures to ensure thechannel is clear before transmitting data. In some cases, operations inunlicensed bands may be based on a CA configuration in conjunction withCCs operating in a licensed band. Operations in unlicensed spectrum mayinclude downlink transmissions, uplink transmissions, or both. Duplexingin unlicensed spectrum may be based on FDD, TDD or a combination ofboth.

A transmitting device (e.g., a base station 105) may broadcast controlinformation including one or more control channels, such as a physicalbroadcast control channel (PBCH); a primary synchronization signal(PSS); a secondary synchronization signal (SSS); a physical controlformat indicator channel (PCFICH); a physical HARQ indicator channel(PHICH); and/or a physical downlink control channel (PDCCH), etc., toone or more receiving devices (e.g., UEs 115). The PHICH carries HARQfeedback transmissions such as an ACK or NACK. HARQ may involve checkingpacket transmissions at the receiving device for accuracy, and ifconfirmed, an ACK may be transmitted, whereas if not confirmed, a NACKmay be transmitted. In response to a NACK, the transmitting device maysend a HARQ retransmission, which may implement chase combining,incremental redundancy, etc. HARQ retransmission may be performed foruplink traffic and downlink traffic.

Uplink and downlink transmissions may generally utilize a suitable errorcorrecting block code. In a typical block code (i.e., a codeword), aninformation message or sequence is split up into CBs, and an encoder atthe transmitting device then mathematically adds redundancy to theinformation message. Exploitation of this redundancy in the encodedinformation message can improve the reliability of the message, enablingcorrection for any bit errors that may occur due to the noise. Someexamples of error correcting codes include Hamming codes,Bose-Chaudhuri-Hocquenghem (BCH) codes, turbo codes, low-density paritycheck (LDPC) codes, and polar codes. Various implementations of basestations 105 and UEs 115 may include suitable hardware and capabilities(e.g., an encoder and/or decoder) to utilize any one or more of theseerror correcting codes for wireless communication.

In some cases, multiple codewords may be utilized for uplink and/ordownlink transmissions. The number of codewords utilized may depend on arank (e.g., a number of spatial layers used for transmissions). Thenumber of spatial layers used for transmission may correspond to thenumber of physical antennas of the transmitting device or the number ofantenna ports or virtual antennas of the transmitting device. Each ofthe multiple codewords may be transmitted using one or more sets ofspatial layers (e.g., based on channel conditions, number of codewords,number of transmitting antennas). For example, for a rank of 1-4, onecodeword may be transmitted (e.g., over a single spatial layer) and fora rank of 5-8, two codewords may be transmitted over multiple or a setof spatial layers. A base station 105 may dynamically select the rankaccording to channel conditions. Each codeword may have a differentmodulation and coding scheme (MCS), which may result in different TBsize and number of CBs.

As discussed previously, the CBs may be grouped together into CBGs. Ifone or more CBs within a CBG are not successfully transmitted, areceiving device (i.e., a UE 115) may transmit a NACK feedback bit forthe corresponding CBG, and a transmitting device (i.e., a base station105) may send a HARQ retransmission of that particular CBG. If theunsuccessfully transmitted CBs are located within multiple CBGs, eachaffected CBG may be retransmitted. Rather than each TB having anassociated feedback bit, each CBG may have an associated ACK/NACKfeedback bit. However, the number of ACK/NACK feedback bits may be fixedwhether one or two codewords are transmitted (e.g., in order to avoidblind decoding assuming different lengths for either physical uplinkcontrol channels (PUCCH) or PDCCH).

Wireless communications system 100 may support efficient techniques totransmit ACK/NACK feedback for multiple codewords using a fixed numberof ACK/NACK feedback bits. In some cases, an ACK/NACK feedback bit maybe utilized for corresponding CBGs of each codeword. For example, afirst CBG of a first codeword may be grouped together with a first CBGof a second codeword, and if a CB within either CBG is unsuccessfullytransmitted, both CBGs may be retransmitted together. Alternatively,multiple CBGs within each codeword may be bundled together for eachACK/NACK feedback bit. In other cases, additional bits may be added tothe ACK/NACK feedback bits to indicate for which codeword, or both, theACK/NACK feedback applies.

FIG. 2 illustrates an example of a wireless communications system 200that supports overlapping code block groups for multiple codewords inaccordance with various aspects of the present disclosure. In someexamples, wireless communications system 200 may implement aspects ofwireless communications system 100. Wireless communications system 200may include a base station 105-a and a UE 115-a, which may be examplesof corresponding base stations 105 and UEs 115 as described withreference to FIG. 1. Base station 105-a may provide communicationcoverage for a coverage area 110-a. Base station 105-a and UE 115-a maycommunicate on resources of a communication link 205. The communicationsmay include a first codeword 210-a and a second codeword 210-b.

Base station 105-a may utilize multiple spatial layers (e.g., multipleantenna ports) to transmit codewords 210. For example, base station105-a may transmit codeword 210-a using a first spatial layer overcommunication link 205-a and may also transmit codeword 210-b using asecond spatial layer over communication link 205-b. The transmission ofthe two codewords 210 may occur at the same time (e.g., within the sameTTI) or at different times. In some cases, a single codeword 210 may betransmitted over multiple spatial layers. For instance, codeword 210-amay be transmitted using four spatial layers by transmitting everyfourth bit of codeword 210-a on one layer.

Communication links 205-a and 205-b may utilize the same frequencyresources (e.g., subcarriers) for transmission of the codewords 210 ormay each utilize different frequency resources. In some examples,communication links 205-a and 205-b may correspond to different antennasof the transmitting device (e.g., base station 105-a), which may bereceived at a receiving device (e.g., UE 115-a) over one or moreantennas.

UE 115-a may transmit codeword 210-a and codeword 210-b to base station105-a on multiple antenna ports, which may correspond to the number ofspatial layers used by the base station 105-a for transmission. Whentransmitting multiple codewords 210 using multiple spatial layers, bothcodewords 210 may be received at approximately the same time.

To determine the number of layers for transmission, a rank indicator(RI) may be transmitted (e.g., from UE 115-a to base station 105-a),which may be used to indicate the number of layers the UE 115-a is ableto successfully receive. The RI may be determined based on channelconditions and the number of layers for transmission may be determinedbased on the RI. The number of layers may then be transmitted by thebase station 105-a (e.g., over a PDCCH on resources of communicationlink 205-a or 205-b). The PDCCH may indicate a number of layers (i.e., arank) for one or more subsequent transmissions. In some cases, the PDCCHmay also indicate a number of CBGs and codeword configurations forcodewords 210 and each codeword 210 may have a different MCS, which mayresult in different TB size and a different number of CBs for differentTBs.

FIG. 3 illustrates an example of a codeword 300 that supportsoverlapping code block groups for multiple codewords in accordance withvarious aspects of the present disclosure. In some examples, codeword300 may implement aspects of wireless communications system 100.Codeword 300 may be transmitted over a slot 305 and may span a pluralityof symbols following a PDCCH 310. In this example, a CBG configurationmay be used to group CBs of a TB using time boundaries (e.g., OFDMsymbols 1 through 12).

PDCCH 310 may indicate a rank for the upcoming transmissions, as well asthe size of a TB of codeword 300. CBGs 315 may be defined by boundariesin time-frequency resources (e.g., OFDM symbols). In the example of FIG.3, CBGs 315 may utilize symbol boundaries to separate each CBG 315, suchthat each symbol following PDCCH 310 is associated with a respective CBG315. For instance, the first symbol following PDCCH 310 may correspondto CBG 315-a, the second symbol following PDCCH 310 may correspond toCBG 315-b, etc. and so on, where the last symbol of slot 305 correspondsto CBG 315-n. While 12 CBGs 315 are depicted in FIG. 2, the number ofsymbols may vary according to subcarrier spacing, symbol duration, slotduration, or other parameters.

During transmission of codeword 300, interference 320 may cause one ormore CBs within a subset of CBGs 315 to be unsuccessfully decoded at thereceiver. As a result, one or more NACK feedback bits may be transmittedto indicate the CBGs 315 with unsuccessfully decoded CBs. In order toreduce the number of CBs that may be retransmitted, an overlapping CBGdesign for CB grouping may be utilized, such that CBs on the boundarybetween two adjacent CBGs 315 may be included in both of the adjacentCBGs 315. As interference 320 may be bursty, and if multiple CBGs areconfigured to span a symbol boundary, the bursty interference may affectmore CBs of the CBGs. For example, CBGs 315 may be configured such thatCBs that fall on the boundary between adjacent CBGs 315 may overlap. Afirst CBG 315-a may include, for instance, CBs 0-5 and a second CBG315-b may include CBs 5-10 with CB 5 overlapping between the first CBG315-a and the second CBG 315-b. A third CBG 315-c may include CBs 10-15with CB 10 overlapping between the second and third CBGs, and so on. Byutilizing the overlapping pattern, a smaller number of CBs and/or CBGsmay be retransmitted. For example, if interference 320 affects symbols 6and 7 as illustrated, the CBGs associated with symbols 6 and 7 may beretransmitted, which may include portions of some CBs that are in eitheror both of symbols 5 and 8. The CBs that overlap either of symbols 5 or8 may also be retransmitted. However, if CBGs are defined by numbers ofCBs without regard to symbol boundaries, there may be three CBGs thatmay need to have all CBs of the CBGs retransmitted, which may be asubstantially greater number of CBs for the same approximate CBG size.

FIG. 4 illustrates an example of a CBG configuration 400 that supportsoverlapping code block groups for multiple codewords in accordance withvarious aspects of the present disclosure. In some examples, CBGconfiguration 400 may be implemented by aspects of wirelesscommunications system 100 such as base stations 105 or UEs 115. CBGconfiguration 400 may include a number of CBs 405 and CBGs 415 within aslot 305-a, which may be examples of CBGs 315 as described in FIG. 3.CBG configuration 400 illustrates an overlapping CB grouping for CBGs415.

As shown, each CBG 415 may include CBs that overlap with a precedingand/or subsequent CBG 415. CBG 415-a may represent the first CBG 415within a codeword. As such, CBG 415-a may only have one overlapping CBwith a following CBG. For example, CB 405-a may be partially within CBG415-a and CBG 415-b. Additionally, CBG 415-b may share CBs with both CBG415-a and a following CBG. For example, CB 405-a spans portions of CBG415-a and 415-b while CB 405-d spans portions of CBG 415-b and CBG415-c. Similar overlapping occurs up to CBG 415-n, which may only shareoverlapping CB N with a preceding CBG 415 (not shown).

By utilizing an overlapping CB pattern, the number of total CBs to beretransmitted as a result of interference may be reduced. For example,interference or other channel conditions may cause signal for the secondsymbol period of CBG 415-b to be degraded, which may cause CBs 405-a,405-b, 405-c, and 405-d to be unsuccessfully decoded at the receivingdevice. When the NACK feedback is retransmitted for CBG 415-b, thetransmitter may know to retransmit all CBs that are at least partiallyoverlapping with CBG 415-b. If, however, CBGs were defined by a numberof CBs (e.g., the CBs are substantially uniformly split into CBGswithout regard for symbol boundaries), interference that degrades thesignal for the second symbol period may cause CBs that span portions oftwo CBGs to be unsuccessfully decoded at the receiving device. Thus, thereceiver would send a NACK for two CBGs, and all CBs of those CBGs wouldneed to be retransmitted, even where several CBs within each of the twoCBGs were actually decoded successfully.

The number of CBs within the slot 305-a may be determined by the TB sizeand the CB size (e.g., data may be segmented into CBs of the same orsimilar size). The TB size may depend on the amount of resources grantedwithin the slot 305-a and the modulation and coding scheme.Additionally, the number of CBs within CBGs 415 of different codewordsmay vary and be specific to each codeword.

FIG. 5 illustrate example codeword configuration 500 that supportsoverlapping code block groups for multiple codewords in accordance withvarious aspects of the present disclosure. In some examples, codewordconfiguration 500 may be implemented by aspects of wirelesscommunications system 100 including base stations 105 or UEs 115.Codeword configuration 500 may include a first codeword 505-a and asecond codeword 505-b, which may be transmitted over multiple spatiallayers. For example, if the rank of a transmission is greater than athreshold (e.g., 2 spatial layers, 4 spatial layers), the number ofspatial layers may be split into sets of spatial layers, where the firstcodeword 505-a is transmitted over a first set of spatial layers and thesecond codeword 505-b is transmitted over a second set of spatiallayers. Codeword 505-a may include CBGs 515 and codeword 505-b mayinclude CBGs 525, which may be examples of CBGs 415 as described withreference to FIG. 4. Codeword configurations 500 may illustratetechniques to group CBGs 515 and CBGs 525 in order to maintain a fixednumber of ACK/NACK feedback bits.

A resource grant for the slot may be carried in one or both of PDCCH510-a or PDCCH 510-b. The resource grant may indicate the TB size forcodeword 505-a and codeword 505-b as well as the layer assignment (e.g.,for a 6-layer transmission, codeword 505-a may be carried by threelayers and codeword 505-b may be carried by a different set of threelayers). The TB sizes for codewords 505-a and 505-b may indicate thenumber CBs within codewords 505-a and 505-b. Similarly, PDCCH 510-b mayindicate the number of CBGs 525 and the number of CBs within each CBG525 for codeword 505-b. The number of CBGs 515 for codeword 505-a may bethe same as the number of CBGs 525 for codeword 505-b. However, thenumber of CBs for each codeword 505 may be unique to each codeword 505(e.g., based on different TB sizes). As such, the number of CBs per CBG515 and the number of CBs per CBG 525 may differ. Each CBG may utilizethe CB overlapping pattern as described in FIG. 4.

As described in FIG. 3, CBGs 515 and 525 may utilize symbol boundariesto separate CBs in each CBG 515 and 525, respectively. The same boundarymay apply for the CBGs of both codeword 505-a and codeword 505-b. Byutilizing the same symbol boundaries and the same number of CBGs,dynamic switching between one codeword 505 and two codewords 505 may besupported. Additionally, by utilizing the same number of CBGs and symbolboundaries, CBGs 515 and 525 may be bundled together within their symbolboundaries for each ACK/NACK feedback bit. For example, CBG 515-a ofcodeword 505-a may be combined with CBG 525-a of codeword 505-b for asingle ACK/NACK feedback bit, CBG 515-b and CBG 525-b may be combinedfor an ACK/NACK feedback bit, and so on up to CBG 515-n and CBG 525-n.

Similar to FIG. 3, an interference 520 may lead to certain CBs within asubset of CBGs 515 and 525 to be unsuccessfully transmitted.Interference 520-a may affect CBGs 515 and interference 520-b may affectCBGs 525. In some examples, interference 520 may affect the same CBGswithin each codeword 505. Therefore, by grouping the same numbered CBG515 with its respective CBG 525, which both may be affected byinterference 520, the number of ACK/NACK feedback bits may be reduced.

FIG. 6 illustrates example CBG configurations 600 that supportoverlapping code block groups for multiple codewords in accordance withvarious aspects of the present disclosure. In some examples, CBGconfigurations 600 may implement aspects of wireless communicationssystem 100. CBG configurations 600 may include a first codeword 605-aand a second codeword 605-b, which may be examples of codewords 300 or505 as described with reference to FIGS. 3 and 5, respectively. Codeword605-a may include CBGs 615 and codeword 605-b may include CBGs 625,which may be examples of CBGs 415 and CBGs 515 and 525 as described withreference to FIGS. 4 and 5, respectively. The number of CBGs 615 andCBGs 625 may be the same. CBG configurations 600 may illustratetechniques for bundling CBGs 615 and 625 together separately within eachcodeword 605 while maintaining a fixed number of ACK/NACK feedback bits.

Codeword 605-a and codeword 605-b may have separate MCS control, whichmay result in both being affected by a type of interference differently.For example, different outer loop backoffs for each codeword 605 orinterference hitting some spatial layers may result in CBs of codeword605-a to fail, but not CBs of codeword 605-b, or vice-versa. CBGs 615and 625 may utilize symbol boundaries to separate CBs in each CBG asdescribed in FIGS. 3 and 5. CBG bundles 610 may combine CBGs within eachcodeword 605, where bundle 610-a may indicate two CBGs bundled together,bundle 610-b may indicate a single CBG, and bundle 610-c may indicatethree CBGs bundled together.

In some cases, bundles 610 may be determined by a uniform split of CBGbundles between codeword 605-a and codeword 605-b. For example, when thenumber of CBGs per codeword 605 is even, CBGs 615 and 625 may be bundledinto bundles of two CBGs (e.g., bundle 610-a), so that every two CBGswithin a codeword 605 share one ACK/NACK feedback bit. Therefore, thenumber of ACK/NACK bits per codeword 605 is halved, resulting in thesame total number of ACK/NACK feedback bits overall. However, if thenumber of CBGs per codeword 605 is odd, bundles of two CBGs may beutilized until no more bundles of two may be formed, and such that a CBGbundle 610 does not span CBGs from both codeword 605-a and codeword605-b. For example, if the number of CBGs per codeword 605 is nine,codeword 605-a may include five total bundles with four bundles 610-a oftwo CBGs 615 and one CBG bundle 610-b of one CBG 615. Additionally,codeword 605-b may include four total bundles with three CBG bindles610-a of CBGs 625 and one CBG bundle 610-c of three CBGs 625. The ninebundles 610 may each correspond to a different ACK/NACK feedback bit.

In other cases, bundles 610 may be determined by a non-uniform split ofCBG bundles between codeword 605-a and codeword 605-b by approximatelyequalizing the number of CBs in each CBG bundle 610. The MCS for eachcodeword 605 may be very different, resulting in the number of CBs perCBG to be different for each codeword 605. The CBG bundles 610 may besplit between codewords 605-a and 605-b by counting the total number ofCBs in each codeword 605 and proportionally splitting CBG bundles 610.For example, codeword 605-a may have 61 CBs in 12 CBGs 615, and codeword605-b may have 39 CBs in 12 CBGs 625. Therefore, there is a total of 100CBs that may be divided among 12 CBGs bundles, where codeword 605-a hasapproximately 60% of the total CBs (i.e., 61/100), and codeword 605-bhas approximately 40% of the total CBs (i.e., 39/100). Thus, eight CBGbundles 610 may be formed for codeword 605-a (i.e., 60% of 12 CBGbundles rounded up), and four CBG bundles 610 may be formed for codeword605-b (i.e., 40% of 12 CBG bundles rounded down). After the CBG bundles610 have been proportioned for each codeword 605, the CBGs may bebundled uniformly within each codeword 605. For example, the eight CBGbundles 610 proportioned for codeword 605-a may include four CBG bundles610-a of two CBGs 615 each and four CBG bundles 610-b of one CBG 615each. Additionally, the four CBG bundles 610 proportioned for codeword605-b may include four CBG bundles 610-c of three CBGs 625 each.

Alternatively, the number of CBs may be split among a number of CBGs forboth codewords 605 based on the total number of CBs between bothcodewords 605. For example, codeword 605-a may have 100 CBs, andcodeword 605-b may have 50 CBs. The total number of 150 CBs may be splitamong 10 total CBGs. Similar to above, the number of CBGs per codeword605 may be determined proportionally. Therefore, codeword 605-a mayinclude seven CBGs 615 (i.e., 100/150 of 10 CBGs rounded up), andcodeword 605-b may include the remaining three CBGs 625. After the CBGshave been proportioned for each codeword 605, the number of CBs per CBGmay be divided out in approximately a uniform way. For example, codeword605-a may split its 100 CBs into the proportioned seven CBGs 615 withtwo CBGs 615 having 15 CBs each and five CBGs having 14 CBs each.Additionally, codeword 605-b may split its 50 CBs into the proportionedthree CBGs 625 with two CBGs 625 having 17 CBs each and one CBG 625having 16 CBs.

In other cases, additional bits may be added to the ACK/NACK feedbackbits to provide a bitmap to indicate for which codewords 605 theACK/NACK feedback bits are intended. For example, if both bits are one(i.e., 11), the ACK/NACK feedback bits may be for both codeword 605-aand 605-b. In such cases, the CBGs of both codewords 605 may be combinedas described with reference to FIG. 5. Additionally or alternatively, ifonly one bit is one (i.e., 10 or 01), the ACK/NACK feedback bits mayapply to only one codeword 605, while the other codeword 605 all passes.For example, if the two bits are “10,” the ACK/NACK feedback may applyto codeword 605-a, and codeword 605-b may be assumed to have beentransmitted correctly. If both bits are zero (i.e., 00), it may indicateonly one codeword 605 is transmitted.

FIG. 7 shows a block diagram 700 of a wireless device 705 that supportsoverlapping code block groups for multiple codewords in accordance withaspects of the present disclosure. Wireless device 705 may be an exampleof aspects of a base station 105 or a UE 115 as described herein.Wireless device 705 may include receiver 710, communications manager715, and transmitter 720. Wireless device 705 may also include aprocessor. Each of these components may be in communication with oneanother (e.g., via one or more buses).

Receiver 710 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to overlappingcode block groups for multiple codewords, etc.). Information may bepassed on to other components of the device. The receiver 710 may be anexample of aspects of the transceiver 1035 described with reference toFIG. 10. The receiver 710 may utilize a single antenna or a set ofantennas.

Communications manager 715 may be an example of aspects of thecommunications manager 1015 described with reference to FIG. 10.Communications manager 715 and/or at least some of its varioussub-components may be implemented in hardware, software executed by aprocessor, firmware, or any combination thereof. If implemented insoftware executed by a processor, the functions of the communicationsmanager 715 and/or at least some of its various sub-components may beexecuted by a general-purpose processor, a digital signal processor(DSP), an application-specific integrated circuit (ASIC), anfield-programmable gate array (FPGA) or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described in thepresent disclosure.

The communications manager 715 and/or at least some of its varioussub-components may be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations by one or more physical devices. In someexamples, communications manager 715 and/or at least some of its varioussub-components may be a separate and distinct component in accordancewith various aspects of the present disclosure. In other examples,communications manager 715 and/or at least some of its varioussub-components may be combined with one or more other hardwarecomponents, including but not limited to an I/O component, atransceiver, a network server, another computing device, one or moreother components described in the present disclosure, or a combinationthereof in accordance with various aspects of the present disclosure.

Communications manager 715 may receive a transmission including a firstcodeword received over a first set of layers and a second codewordreceived over a second set of layers, where the first codeword mayinclude a first set of code blocks and the second codeword may include asecond set of code blocks. Communications manager 715 may perform adecoding operation on the first and second pluralities of code blocks ofthe transmission and determine an association between a set of feedbackbits for the transmission and the first and second pluralities of codeblocks based on a code block group configuration for the first andsecond codewords. Further, a number of bits of the set of feedback bitsmay correspond to a number of code blocks for a single layertransmission. Communications manager 715 may transmit a messageincluding the set of feedback bits based on a result of the decodingoperation and the determined association.

The communications manager 715 may also transmit, in a firsttransmission, a first codeword over a first set of layers and a secondcodeword over a second set of layers, where the first codeword mayinclude a first set of code blocks and the second codeword may include asecond set of code blocks. Communications manager 715 may receive amessage including a set of feedback bits for the first codeword and thesecond codeword, where the set of feedback bits may be associated withthe first and second pluralities of code blocks based on a code blockgroup configuration for the first and second codewords. Further, anumber of bits of the set of feedback bits may correspond to a number ofcode blocks for a single layer transmission. Communications manager 715may determine whether to retransmit a code block of the first or secondpluralities of code blocks based on the set of feedback bits.

Transmitter 720 may transmit signals generated by other components ofthe device. In some examples, the transmitter 720 may be collocated witha receiver 710 in a transceiver module. For example, the transmitter 720may be an example of aspects of the transceiver 1035 described withreference to FIG. 10. The transmitter 720 may utilize a single antennaor a set of antennas.

FIG. 8 shows a block diagram 800 of a wireless device 805 that supportsoverlapping code block groups for multiple codewords in accordance withaspects of the present disclosure. Wireless device 805 may be an exampleof aspects of a wireless device 705, a base station 105, or a UE 115 asdescribed with reference to FIG. 7. Wireless device 805 may includereceiver 810, communications manager 815, and transmitter 820. Wirelessdevice 805 may also include a processor. Each of these components may bein communication with one another (e.g., via one or more buses).

Receiver 810 may receive information such as packets, user data, orcontrol information associated with various information channels (e.g.,control channels, data channels, and information related to overlappingcode block groups for multiple codewords, etc.). Information may bepassed on to other components of the device. The receiver 810 may be anexample of aspects of the transceiver 1035 described with reference toFIG. 10. The receiver 810 may utilize a single antenna or a set ofantennas.

Communications manager 815 may be an example of aspects of thecommunications manager 1015 described with reference to FIG. 10.Communications manager 815 may also include codeword receiver 825,decoder 830, association component 835, message transmitter 840,codeword transmitter 845, message receiver 850, and retransmissioncomponent 855.

Codeword receiver 825 may receive a transmission including a firstcodeword received over a first set of layers and a second codewordreceived over a second set of layers, where the first codeword mayinclude a first set of code blocks and the second codeword may include asecond set of code blocks. In some cases, a number of code blocks of thefirst set of code blocks may be different from a number of code blocksof the second set of code blocks.

Decoder 830 may perform a decoding operation on the first and secondpluralities of code blocks of the transmission.

Association component 835 may determine an association between a set offeedback bits for the transmission and the first and second pluralitiesof code blocks based on a code block group configuration for the firstand second codewords. Further, a number of bits of the set of feedbackbits may correspond to a number of code blocks for a single layertransmission. Association component 835 may uniformly split the firstset of code blocks into the first set of code block groups and thesecond set of code blocks into the second set of code block groups andassociate each feedback bit of the set of feedback bits with arespective bundled code block group. In some cases, associationcomponent 835 may split the number of code block group bundles into afirst set of code block group bundles for the first codeword and asecond set of code block group bundles for the second codeword. Further,association component 835 may split the number of code block groups intoa first set of code block groups for the first codeword and a second setof code block groups for the second codeword in proportion to a numberof code blocks in the first codeword and a number of code blocks in thesecond codeword. In some cases, Association component 835 may bundleconsecutive code block groups of the first codeword and the secondcodeword into the first and second sets of code block group bundles.

In some cases, determining the association between the set of feedbackbits and the first and second pluralities of code blocks may include oneor more of: bundling respective code block groups of the first andsecond codewords, determining a number of code block group bundles basedon the number of bits of the set of feedback bits, or determining anumber of code block groups based on the number of bits of the set offeedback bits. Determining the code block group configuration mayinclude assigning the first and second pluralities of code blocks tocode block groups according to time resource boundaries for the firstand second codewords. Alternatively, determining the code block groupconfiguration may include assigning the first and second pluralities ofcode blocks to code block groups according to a uniform distribution. Insome cases, the number of code block group bundles may be uniformlysplit into the first set of code block group bundles and the second setof code block group bundles. Alternatively, the number of code blockgroup bundles may be split into the first set of code block groupbundles and the second set of code block group bundles in proportion toa number of code blocks in the first codeword and a number of codeblocks in the second codeword.

Message transmitter 840 may transmit a message including the set offeedback bits based on a result of the decoding operation and thedetermined association. In some cases, the message may include afeedback application bitmap indicating the applicability of the set offeedback bits to one or both of the first codeword or to the secondcodeword. In some examples, the feedback application bitmap indicateswhether all code block groups of one or both of the first codeword orthe second codeword failed the decoding operation.

Codeword transmitter 845 may transmit, in a first transmission, a firstcodeword over a first set of layers and a second codeword over a secondset of layers, where the first codeword may include a first set of codeblocks and the second codeword may include a second set of code blocks.In some cases, a number of code blocks of the first set of code blocksis different from a number of code blocks of the second set of codeblocks.

Message receiver 850 may receive a message including a set of feedbackbits for the first codeword and the second codeword, where the set offeedback bits may be associated with the first and second pluralities ofcode blocks based on a code block group configuration for the first andsecond codewords. Further, a number of bits of the set of feedback bitsmay correspond to a number of code blocks for a single layertransmission. In some cases, determining the code block groupconfiguration may include assigning the first and second pluralities ofcode blocks to code block groups according to time resource boundariesfor the first and second codewords. In some examples, each code blockgroup of the code block groups spans a symbol of a set of symbols overwhich the first transmission is transmitted. In some aspects, themessage may include a feedback application bitmap indicating theapplicability of the set of feedback bits to one or both of the firstcodeword or to the second codeword. In some instances, the feedbackapplication bitmap indicates whether all code block groups of one orboth of the first codeword or the second codeword failed the decodingoperation. In some cases, determining the code block group configurationmay include assigning the first and second pluralities of code blocks tocode block groups according to a uniform distribution.

Retransmission component 855 may determine whether to retransmit a codeblock of the first or second pluralities of code blocks based on the setof feedback bits and uniformly split the first set of code blocks intothe first set of code block groups and the second set of code blocksinto the second set of code block groups. Retransmission component 855may associate each feedback bit of the set of feedback bits with arespective bundled code block group and split the number of code blockgroup bundles into a first set of code block group bundles for the firstcodeword and a second set of code block group bundles for the secondcodeword. In some cases, retransmission component 855 may split thenumber of code block groups into a first set of code block groups forthe first codeword and a second set of code block groups for the secondcodeword in proportion to a number of code blocks in the first codewordand a number of code blocks in the second codeword. Retransmissioncomponent 855 may bundle consecutive code block groups of the firstcodeword and the second codeword into the first and second sets of codeblock group bundles.

In some examples, determining whether to retransmit the code block mayinclude determining a number of code block group bundles based on thenumber of bits of the set of feedback bits. In some aspects, determiningwhether to retransmit the code block may include bundling respectivecode block groups of the first and second codewords. In some instances,the number of code block group bundles are uniformly split into thefirst set of code block group bundles and the second set of code blockgroup bundles. In some cases, the number of code block group bundles aresplit into the first set of code block group bundles and the second setof code block group bundles in proportion to a number of code blocks inthe first codeword and a number of code blocks in the second codeword.In some cases, determining whether to retransmit the code block mayinclude determining a number of code block groups based on the number ofbits of the set of feedback bits.

Transmitter 820 may transmit signals generated by other components ofthe device. In some examples, the transmitter 820 may be collocated witha receiver 810 in a transceiver module. For example, the transmitter 820may be an example of aspects of the transceiver 1035 described withreference to FIG. 10. The transmitter 820 may utilize a single antennaor a set of antennas.

FIG. 9 shows a block diagram 900 of a communications manager 915 thatsupports overlapping code block groups for multiple codewords inaccordance with aspects of the present disclosure. The communicationsmanager 915 may be an example of aspects of a communications manager715, a communications manager 815, or a communications manager 1015described with reference to FIGS. 7, 8, and 10. The communicationsmanager 915 may include codeword receiver 920, decoder 925, associationcomponent 930, message transmitter 935, codeword transmitter 940,message receiver 945, retransmission component 950, and feedback bitcomponent 955. Each of these modules may communicate, directly orindirectly, with one another (e.g., via one or more buses).

Codeword receiver 920 may receive a transmission including a firstcodeword received over a first set of layers and a second codewordreceived over a second set of layers, where the first codeword mayinclude a first set of code blocks and the second codeword may include asecond set of code blocks. In some cases, a number of code blocks of thefirst set of code blocks is different from a number of code blocks ofthe second set of code blocks.

Decoder 925 may perform a decoding operation on the first and secondpluralities of code blocks of the transmission.

Association component 930 may determine an association between a set offeedback bits for the transmission and the first and second pluralitiesof code blocks based on a code block group configuration for the firstand second codewords. Further, a number of bits of the set of feedbackbits may correspond to a number of code blocks for a single layertransmission. Association component 930 may uniformly split the firstset of code blocks into the first set of code block groups and thesecond set of code blocks into the second set of code block groups andassociate each feedback bit of the set of feedback bits with arespective bundled code block group. Association component 930 may splitthe number of code block group bundles into a first set of code blockgroup bundles for the first codeword and a second set of code blockgroup bundles for the second codeword. In some cases, associationcomponent 930 may split the number of code block groups into a first setof code block groups for the first codeword and a second set of codeblock groups for the second codeword in proportion to a number of codeblocks in the first codeword and a number of code blocks in the secondcodeword. Retransmission component 855 may bundle consecutive code blockgroups of the first codeword and the second codeword into the first andsecond sets of code block group bundles.

In some cases, determining the association between the set of feedbackbits and the first and second pluralities of code blocks may includebundling respective code block groups of the first and second codewords.In some examples, determining the association between the set offeedback bits and the first and second pluralities of code blocks mayinclude determining a number of code block group bundles based on thenumber of bits of the set of feedback bits. In some aspects, the codeblock group configuration may include assigning the first and secondpluralities of code blocks to code block groups according to timeresource boundaries for the first and second codewords. In someinstances, the number of code block group bundles are uniformly splitinto the first set of code block group bundles and the second set ofcode block group bundles. In some cases, the number of code block groupbundles are split into the first set of code block group bundles and thesecond set of code block group bundles in proportion to a number of codeblocks in the first codeword and a number of code blocks in the secondcodeword. In some examples, determining the code block groupconfiguration may include assigning the first and second pluralities ofcode blocks to code block groups according to a uniform distribution. Insome aspects, determining the association between the feedback bits andthe first and second pluralities of code blocks may include determininga number of code block groups based on the number of bits of the set offeedback bits.

Message transmitter 935 may transmit a message including the set offeedback bits based on a result of the decoding operation and thedetermined association. In some cases, the message may include afeedback application bitmap indicating the applicability of the set offeedback bits to one or both of the first codeword or to the secondcodeword. In some cases, the feedback application bitmap indicateswhether all code block groups of one or both of the first codeword orthe second codeword failed the decoding operation.

Codeword transmitter 940 may transmit, in a first transmission, a firstcodeword over a first set of layers and a second codeword over a secondset of layers, where the first codeword may include a first set of codeblocks and the second codeword may include a second set of code blocks.In some cases, a number of code blocks of the first set of code blocksis different from a number of code blocks of the second set of codeblocks.

Message receiver 945 may receive a message including a set of feedbackbits for the first codeword and the second codeword, where the set offeedback bits may be associated with the first and second pluralities ofcode blocks based on a code block group configuration for the first andsecond codewords. Further, a number of bits of the set of feedback bitsmay correspond to a number of code blocks for a single layertransmission. In some cases, determining the code block groupconfiguration may include assigning the first and second pluralities ofcode blocks to code block groups according to time resource boundariesfor the first and second codewords. In some examples, each code blockgroup of the code block groups spans a symbol of a set of symbols overwhich the first transmission is transmitted. In some aspects, themessage may include a feedback application bitmap indicating theapplicability of the set of feedback bits to one or both of the firstcodeword or to the second codeword. In some instances, the feedbackapplication bitmap indicates whether all code block groups of one orboth of the first codeword or the second codeword failed the decodingoperation. In some cases, determining the code block group configurationmay include assigning the first and second pluralities of code blocks tocode block groups according to a uniform distribution.

Retransmission component 950 may determine whether to retransmit a codeblock of the first or second pluralities of code blocks based on the setof feedback bits. Retransmission component 950 may uniformly split thefirst set of code blocks into the first set of code block groups and thesecond set of code blocks into the second set of code block groups andassociate each feedback bit of the set of feedback bits with arespective bundled code block group. Retransmission component 950 maysplit the number of code block group bundles into a first set of codeblock group bundles for the first codeword and a second set of codeblock group bundles for the second codeword. In some cases,retransmission component 950 may split the number of code block groupsinto a first set of code block groups for the first codeword and asecond set of code block groups for the second codeword in proportion toa number of code blocks in the first codeword and a number of codeblocks in the second codeword. Retransmission component 950 may bundleconsecutive code block groups of the first codeword and the secondcodeword into the first and second sets of code block group bundles.

In some cases, determining whether to retransmit the code block mayinclude determining a number of code block group bundles based on thenumber of bits of the set of feedback bits. In some examples,determining whether to retransmit the code block may include bundlingrespective code block groups of the first and second codewords. In someaspects, the number of code block group bundles may be uniformly splitinto the first set of code block group bundles and the second set ofcode block group bundles. In some instances, the number of code blockgroup bundles may be split into the first set of code block groupbundles and the second set of code block group bundles in proportion toa number of code blocks in the first codeword and a number of codeblocks in the second codeword. In some cases, determining whether toretransmit the code block may include determining a number of code blockgroups based on the number of bits of the set of feedback bits.

Feedback bit component 955 may determine the number of feedback bitsbased on a number of symbols of the set of symbols, where each codeblock group of the code block groups may span a symbol of the set ofsymbols.

FIG. 10 shows a diagram of a system 1000 including a device 1005 thatsupports overlapping code block groups for multiple codewords inaccordance with aspects of the present disclosure. Device 1005 may be anexample of or include the components of wireless device 705, wirelessdevice 805, a base station 105, or a UE 115 as described above, e.g.,with reference to FIGS. 7 and 8. Device 1005 may include components forbi-directional voice and data communications including components fortransmitting and receiving communications, including communicationsmanager 1015, processor 1020, memory 1025, software 1030, transceiver1035, antenna 1040, and I/O controller 1045. These components may be inelectronic communication via one or more buses (e.g., bus 1010).

The communications manager 1015 may be an example of aspects of acommunications manager 715, a communications manager 815, or acommunications manager 915 described with reference to FIGS. 7, 8, and9.

Processor 1020 may include an intelligent hardware device, (e.g., ageneral-purpose processor, a DSP, a central processing unit (CPU), amicrocontroller, an ASIC, an FPGA, a programmable logic device, adiscrete gate or transistor logic component, a discrete hardwarecomponent, or any combination thereof). In some cases, processor 1020may be configured to operate a memory array using a memory controller.In other cases, a memory controller may be integrated into processor1020. Processor 1020 may be configured to execute computer-readableinstructions stored in a memory to perform various functions (e.g.,functions or tasks supporting overlapping code block groups for multiplecodewords).

Memory 1025 may include random access memory (RAM) and read only memory(ROM). The memory 1025 may store computer-readable, computer-executablesoftware 1030 including instructions that, when executed, cause theprocessor to perform various functions described herein. In some cases,the memory 1025 may contain, among other things, a basic input/outputsystem (BIOS) which may control basic hardware or software operationsuch as the interaction with peripheral components or devices.

Software 1030 may include code to implement aspects of the presentdisclosure, including code to support overlapping code block groups formultiple codewords. Software 1030 may be stored in a non-transitorycomputer-readable medium such as system memory or other memory. In somecases, the software 1030 may not be directly executable by the processorbut may cause a computer (e.g., when compiled and executed) to performfunctions described herein.

Transceiver 1035 may communicate bi-directionally, via one or moreantennas, wired, or wireless links as described above. For example, thetransceiver 1035 may represent a wireless transceiver and maycommunicate bi-directionally with another wireless transceiver. Thetransceiver 1035 may also include a modem to modulate the packets andprovide the modulated packets to the antennas for transmission, and todemodulate packets received from the antennas.

In some cases, the wireless device may include a single antenna 1040.However, in some cases the device may have more than one antenna 1040,which may be capable of concurrently transmitting or receiving multiplewireless transmissions.

I/O controller 1045 may manage input and output signals for device 1005.I/O controller 1045 may also manage peripherals not integrated intodevice 1005. In some cases, I/O controller 1045 may represent a physicalconnection or port to an external peripheral. In some cases, I/Ocontroller 1045 may utilize an operating system such as iOS®, ANDROID®,MS-DOS®, MS-WINDOWS®, OS/2®, UNIX®, LINUX®, or another known operatingsystem. In other cases, I/O controller 1045 may represent or interactwith a modem, a keyboard, a mouse, a touchscreen, or a similar device.In some cases, I/O controller 1045 may be implemented as part of aprocessor. In some cases, a user may interact with device 1005 via I/Ocontroller 1045 or via hardware components controlled by I/O controller1045.

FIG. 11 shows a flowchart illustrating a method 1100 for overlappingcode block groups for multiple codewords in accordance with aspects ofthe present disclosure. The operations of method 1100 may be implementedby a base station 105, a UE 115, or their components as describedherein. For example, the operations of method 1100 may be performed by acommunications manager as described with reference to FIGS. 7 through10. In some examples, a base station 105 or UE 115 may execute a set ofcodes to control the functional elements of the device to perform thefunctions described below. Additionally or alternatively, the basestation 105 or UE 115 may perform aspects of the functions describedbelow using special-purpose hardware.

At block 1105 the base station 105 or UE 115 may receive a transmissionincluding a first codeword received over a first set of layers and asecond codeword received over a second set of layers, where the firstcodeword may include a first plurality of code blocks and the secondcodeword may include a second plurality of code blocks. The operationsof block 1105 may be performed according to the methods describedherein. In certain examples, aspects of the operations of block 1105 maybe performed by a codeword receiver as described with reference to FIGS.7 through 10.

At block 1110 the base station 105 or UE 115 may perform a decodingoperation on the first and second pluralities of code blocks of thetransmission. The operations of block 1110 may be performed according tothe methods described herein. In certain examples, aspects of theoperations of block 1110 may be performed by a decoder as described withreference to FIGS. 7 through 10.

At block 1115 the base station 105 or UE 115 may determine anassociation between a set of feedback bits for the transmission and thefirst and second pluralities of code blocks based on a code block groupconfiguration for the first and second codewords. Further, a number ofbits of the set of feedback bits may correspond to a number of codeblocks for a single layer transmission. The operations of block 1115 maybe performed according to the methods described herein. In certainexamples, aspects of the operations of block 1115 may be performed by anassociation component as described with reference to FIGS. 7 through 10.

At block 1120 the base station 105 or UE 115 may transmit a messageincluding the set of feedback bits based on a result of the decodingoperation and the determined association. The operations of block 1120may be performed according to the methods described herein. In certainexamples, aspects of the operations of block 1120 may be performed by amessage transmitter as described with reference to FIGS. 7 through 10.

FIG. 12 shows a flowchart illustrating a method 1200 for overlappingcode block groups for multiple codewords in accordance with aspects ofthe present disclosure. The operations of method 1200 may be implementedby a base station 105, a UE 115, or their components as describedherein. For example, the operations of method 1200 may be performed by acommunications manager as described with reference to FIGS. 7 through10. In some examples, a base station 105 or a UE 115 may execute a setof codes to control the functional elements of the device to perform thefunctions described below. Additionally or alternatively, the basestation 105 or a UE 115 may perform aspects of the functions describedbelow using special-purpose hardware.

At block 1205 the base station 105 or UE 115 may transmit, in a firsttransmission, a first codeword over a first set of layers and a secondcodeword over a second set of layers, where the first codeword mayinclude a first plurality of code blocks and the second codeword mayinclude a second plurality of code blocks. The operations of block 1205may be performed according to the methods described herein. In certainexamples, aspects of the operations of block 1205 may be performed by acodeword transmitter as described with reference to FIGS. 7 through 10.

At block 1210 the base station 105 or UE 115 may receive a messageincluding a set of feedback bits for the first codeword and the secondcodeword, where the set of feedback bits may be associated with thefirst and second pluralities of code blocks based on a code block groupconfiguration for the first and second codewords. Further, a number ofbits of the set of feedback bits may correspond to a number of codeblocks for a single layer transmission. The operations of block 1210 maybe performed according to the methods described herein. In certainexamples, aspects of the operations of block 1210 may be performed by amessage receiver as described with reference to FIGS. 7 through 10.

At block 1215 the base station 105 or UE 115 may determine whether toretransmit a code block of the first or second pluralities of codeblocks based on the set of feedback bits. The operations of block 1215may be performed according to the methods described herein. In certainexamples, aspects of the operations of block 1215 may be performed by aretransmission component as described with reference to FIGS. 7 through10.

It should be noted that the methods described above describe possibleimplementations, and that the operations and the steps may be rearrangedor otherwise modified and that other implementations are possible.Further, aspects from two or more of the methods may be combined.

Techniques described herein may be used for various wirelesscommunications systems such as code division multiple access (CDMA),time division multiple access (TDMA), frequency division multiple access(FDMA), orthogonal frequency division multiple access (OFDMA), singlecarrier frequency division multiple access (SC-FDMA), and other systems.The terms “system” and “network” are often used interchangeably. A CDMAsystem may implement a radio technology such as CDMA2000, UniversalTerrestrial Radio Access (UTRA), etc. CDMA2000 covers IS-2000, IS-95,and IS-856 standards. IS-2000 Releases may be commonly referred to asCDMA2000 1×, 1×, etc. IS-856 (TIA-856) is commonly referred to asCDMA2000 1×EV-DO, High Rate Packet Data (HRPD), etc. UTRA includesWideband CDMA (WCDMA) and other variants of CDMA. A TDMA system mayimplement a radio technology such as Global System for MobileCommunications (GSM).

An OFDMA system may implement a radio technology such as Ultra MobileBroadband (UMB), Evolved UTRA (E-UTRA), Institute of Electrical andElectronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal MobileTelecommunications System (UMTS). LTE and LTE-A are releases of UMTSthat use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, NR, and GSM aredescribed in documents from the organization named “3rd GenerationPartnership Project” (3GPP). CDMA2000 and UMB are described in documentsfrom an organization named “3rd Generation Partnership Project 2”(3GPP2). The techniques described herein may be used for the systems andradio technologies mentioned above as well as other systems and radiotechnologies. While aspects of an LTE or an NR system may be describedfor purposes of example, and LTE or NR terminology may be used in muchof the description, the techniques described herein are applicablebeyond LTE or NR applications.

In LTE/LTE-A networks, including such networks described herein, theterm evolved node B (eNB) may be generally used to describe the basestations. The wireless communications system or systems described hereinmay include a heterogeneous LTE/LTE-A or NR network in which differenttypes of eNBs provide coverage for various geographical regions. Forexample, each eNB, next generation NodeB (gNB), or base station mayprovide communication coverage for a macro cell, a small cell, or othertypes of cell. The term “cell” may be used to describe a base station, acarrier or component carrier associated with a base station, or acoverage area (e.g., sector, etc.) of a carrier or base station,depending on context.

Base stations may include or may be referred to by those skilled in theart as a base transceiver station, a radio base station, an accesspoint, a radio transceiver, a NodeB, eNodeB (eNB), gNB, Home NodeB, aHome eNodeB, or some other suitable terminology. The geographic coveragearea for a base station may be divided into sectors making up only aportion of the coverage area. The wireless communications system orsystems described herein may include base stations of different types(e.g., macro or small cell base stations). The UEs described herein maybe able to communicate with various types of base stations and networkequipment including macro eNBs, small cell eNBs, gNBs, relay basestations, and the like. There may be overlapping geographic coverageareas for different technologies.

A macro cell generally covers a relatively large geographic area (e.g.,several kilometers in radius) and may allow unrestricted access by UEswith service subscriptions with the network provider. A small cell is alower-powered base station, as compared with a macro cell, that mayoperate in the same or different (e.g., licensed, unlicensed, etc.)frequency bands as macro cells. Small cells may include pico cells,femto cells, and micro cells according to various examples. A pico cell,for example, may cover a small geographic area and may allowunrestricted access by UEs with service subscriptions with the networkprovider. A femto cell may also cover a small geographic area (e.g., ahome) and may provide restricted access by UEs having an associationwith the femto cell (e.g., UEs in a closed subscriber group (CSG), UEsfor users in the home, and the like). An eNB for a macro cell may bereferred to as a macro eNB. An eNB for a small cell may be referred toas a small cell eNB, a pico eNB, a femto eNB, or a home eNB. An eNB maysupport one or multiple (e.g., two, three, four, and the like) cells(e.g., component carriers).

The wireless communications system or systems described herein maysupport synchronous or asynchronous operation. For synchronousoperation, the base stations may have similar frame timing, andtransmissions from different base stations may be approximately alignedin time. For asynchronous operation, the base stations may havedifferent frame timing, and transmissions from different base stationsmay not be aligned in time. The techniques described herein may be usedfor either synchronous or asynchronous operations.

The downlink transmissions described herein may also be called forwardlink transmissions while the uplink transmissions may also be calledreverse link transmissions. Each communication link describedherein—including, for example, wireless communications system 100 and200 of FIGS. 1 and 2—may include one or more carriers, where eachcarrier may be a signal made up of multiple sub-carriers (e.g., waveformsignals of different frequencies).

The description set forth herein, in connection with the appendeddrawings, describes example configurations and does not represent allthe examples that may be implemented or that are within the scope of theclaims. The term “exemplary” used herein means “serving as an example,instance, or illustration,” and not “preferred” or “advantageous overother examples.” The detailed description includes specific details forthe purpose of providing an understanding of the described techniques.These techniques, however, may be practiced without these specificdetails. In some instances, well-known structures and devices are shownin block diagram form in order to avoid obscuring the concepts of thedescribed examples.

In the appended figures, similar components or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If just the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

Information and signals described herein may be represented using any ofa variety of different technologies and techniques. For example, data,instructions, commands, information, signals, bits, symbols, and chipsthat may be referenced throughout the above description may berepresented by voltages, currents, electromagnetic waves, magneticfields or particles, optical fields or particles, or any combinationthereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a DSP, an ASIC, an FPGA or other programmablelogic device, discrete gate or transistor logic, discrete hardwarecomponents, or any combination thereof designed to perform the functionsdescribed herein. A general-purpose processor may be a microprocessor,but in the alternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, multiple microprocessors, one or moremicroprocessors in conjunction with a DSP core, or any other suchconfiguration).

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope of the disclosure and appended claims. For example, due to thenature of software, functions described above can be implemented usingsoftware executed by a processor, hardware, firmware, hardwiring, orcombinations of any of these. Features implementing functions may alsobe physically located at various positions, including being distributedsuch that portions of functions are implemented at different physicallocations. Also, as used herein, including in the claims, “or” as usedin a list of items (for example, a list of items prefaced by a phrasesuch as “at least one of” or “one or more of”) indicates an inclusivelist such that, for example, a list of at least one of A, B, or C meansA or B or C or AB or AC or BC or ABC (i.e., A and B and C). Also, asused herein, the phrase “based on” shall not be construed as a referenceto a closed set of conditions. For example, an exemplary step that isdescribed as “based on condition A” may be based on both a condition Aand a condition B without departing from the scope of the presentdisclosure. In other words, as used herein, the phrase “based on” shallbe construed in the same manner as the phrase “based at least in parton.”

Computer-readable media includes both non-transitory computer storagemedia and communication media including any medium that facilitatestransfer of a computer program from one place to another. Anon-transitory storage medium may be any available medium that can beaccessed by a general purpose or special purpose computer. By way ofexample, and not limitation, non-transitory computer-readable media mayinclude RAM, ROM, electrically erasable programmable read only memory(EEPROM), compact disk (CD) ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any othernon-transitory medium that can be used to carry or store desired programcode means in the form of instructions or data structures and that canbe accessed by a general-purpose or special-purpose computer, or ageneral-purpose or special-purpose processor. Also, any connection isproperly termed a computer-readable medium. For example, if the softwareis transmitted from a website, server, or other remote source using acoaxial cable, fiber optic cable, twisted pair, digital subscriber line(DSL), or wireless technologies such as infrared, radio, and microwave,then the coaxial cable, fiber optic cable, twisted pair, DSL, orwireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,include CD, laser disc, optical disc, digital versatile disc (DVD),floppy disk and Blu-ray disc where disks usually reproduce datamagnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

The description herein is provided to enable a person skilled in the artto make or use the disclosure. Various modifications to the disclosurewill be readily apparent to those skilled in the art, and the genericprinciples defined herein may be applied to other variations withoutdeparting from the scope of the disclosure. Thus, the disclosure is notlimited to the examples and designs described herein, but is to beaccorded the broadest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. A method for wireless communication, comprising:receiving a transmission comprising a first codeword received over afirst set of layers and a second codeword received over a second set oflayers, the first codeword comprising a first plurality of code blocksand the second codeword comprising a second plurality of code blocks;performing a decoding operation on the first and second pluralities ofcode blocks of the transmission; determining an association between aset of feedback bits for the transmission and the first and secondpluralities of code blocks based at least in part on a code block groupconfiguration for the first and second codewords, wherein a number ofbits of the set of feedback bits correspond to a number of code blocksfor a single layer transmission; and transmitting a message comprisingthe set of feedback bits based at least in part on a result of thedecoding operation and the determined association.
 2. The method ofclaim 1, wherein the code block group configuration comprises: assigningthe first and second pluralities of code blocks to code block groupsaccording to time-frequency resource boundaries for the first and secondcodewords.
 3. The method of claim 2, wherein determining the associationbetween the set of feedback bits and the first and second pluralities ofcode blocks comprises: bundling respective code block groups of thefirst and second codewords; and associating each feedback bit of the setof feedback bits with a respective bundled code block group.
 4. Themethod of claim 2, further comprising: determining the number offeedback bits based at least in part on a number of symbols of a set ofsymbols, wherein each code block group of the code block groups spans asymbol of the set of symbols.
 5. The method of claim 2, whereindetermining the association between the set of feedback bits and thefirst and second pluralities of code blocks comprises: determining anumber of code block group bundles based at least in part on the numberof bits of the set of feedback bits; splitting the number of code blockgroup bundles into a first set of code block group bundles for the firstcodeword and a second set of code block group bundles for the secondcodeword; and bundling consecutive code block groups of the firstcodeword and the second codeword into the first and second sets of codeblock group bundles.
 6. The method of claim 5, wherein: the number ofcode block group bundles are uniformly split into the first set of codeblock group bundles and the second set of code block group bundles. 7.The method of claim 5, wherein the number of code block group bundlesare split into the first set of code block group bundles and the secondset of code block group bundles in proportion to a number of code blocksin the first codeword and a number of code blocks in the secondcodeword.
 8. The method of claim 2, wherein the message comprises afeedback application bitmap indicating the applicability of the set offeedback bits to one or both of the first codeword or to the secondcodeword.
 9. The method of claim 8, wherein the feedback applicationbitmap indicates whether all code block groups of one or both of thefirst codeword or the second codeword failed the decoding operation. 10.The method of claim 2, wherein a number of code blocks of the firstplurality of code blocks is different from a number of code blocks ofthe second plurality of code blocks.
 11. The method of claim 1, whereinthe code block group configuration comprises: assigning the first andsecond pluralities of code blocks to code block groups according to auniform distribution.
 12. The method of claim 11, wherein determiningthe association between the feedback bits and the first and secondpluralities of code blocks comprises: determining a number of code blockgroups based at least in part on the number of bits of the set offeedback bits; splitting the number of code block groups into a firstset of code block groups for the first codeword and a second set of codeblock groups for the second codeword in proportion to a number of codeblocks in the first codeword and a number of code blocks in the secondcodeword; and splitting the first plurality of code blocks into thefirst set of code block groups and the second plurality of code blocksinto the second set of code block groups.
 13. A method for wirelesscommunication, comprising: transmitting, in a first transmission, afirst codeword over a first set of layers and a second codeword over asecond set of layers, the first codeword comprising a first plurality ofcode blocks and the second codeword comprising a second plurality ofcode blocks; receiving a message comprising a set of feedback bits forthe first codeword and the second codeword, the set of feedback bitsassociated with the first and second pluralities of code blocks based atleast in part on a code block group configuration for the first andsecond codewords, wherein a number of bits of the set of feedback bitscorrespond to a number of code blocks for a single layer transmission;and determining whether to retransmit a code block of the first orsecond pluralities of code blocks based at least in part on the set offeedback bits.
 14. The method of claim 13, wherein the code block groupconfiguration comprises: assigning the first and second pluralities ofcode blocks to code block groups according to time-frequency resourceboundaries for the first and second codewords.
 15. The method of claim14, wherein determining whether to retransmit the code block comprises:bundling respective code block groups of the first and second codewords;and associating each feedback bit of the set of feedback bits with arespective bundled code block group.
 16. The method of claim 14, whereineach code block group of the code block groups spans a symbol of a setof symbols over which the first transmission is transmitted.
 17. Themethod of claim 14, wherein determining whether to retransmit the codeblock comprises: determining a number of code block group bundles basedat least in part on the number of bits of the set of feedback bits;splitting the number of code block group bundles into a first set ofcode block group bundles for the first codeword and a second set of codeblock group bundles for the second codeword; and bundling consecutivecode block groups of the first codeword and the second codeword into thefirst and second sets of code block group bundles.
 18. The method ofclaim 17, wherein the number of code block group bundles are uniformlysplit into the first set of code block group bundles and the second setof code block group bundles.
 19. The method of claim 17, wherein thenumber of code block group bundles are split into the first set of codeblock group bundles and the second set of code block group bundles inproportion to a number of code blocks in the first codeword and a numberof code blocks in the second codeword.
 20. The method of claim 14,wherein the message comprises a feedback application bitmap indicatingthe applicability of the set of feedback bits to one or both of thefirst codeword or to the second codeword.
 21. The method of claim 20,wherein the feedback application bitmap indicates whether all code blockgroups of one or both of the first codeword or the second codewordfailed the decoding operation.
 22. The method of claim 14, wherein anumber of code blocks of the first plurality of code blocks is differentfrom a number of code blocks of the second plurality of code blocks. 23.The method of claim 13, wherein the code block group configurationcomprises: assigning the first and second pluralities of code blocks tocode block groups according to a uniform distribution.
 24. The method ofclaim 23, wherein determining whether to retransmit the code blockcomprises: determining a number of code block groups based at least inpart on the number of bits of the set of feedback bits; splitting thenumber of code block groups into a first set of code block groups forthe first codeword and a second set of code block groups for the secondcodeword in proportion to a number of code blocks in the first codewordand a number of code blocks in the second codeword; and uniformlysplitting the first plurality of code blocks into the first set of codeblock groups and the second plurality of code blocks into the second setof code block groups.
 25. An apparatus for wireless communication,comprising: a processor; memory in electronic communication with theprocessor; and instructions stored in the memory and operable, whenexecuted by the processor, to cause the apparatus to: receive atransmission comprising a first codeword received over a first set oflayers and a second codeword received over a second set of layers, thefirst codeword comprising a first plurality of code blocks and thesecond codeword comprising a second plurality of code blocks; perform adecoding operation on the first and second pluralities of code blocks ofthe transmission; determine an association between a set of feedbackbits for the transmission and the first and second pluralities of codeblocks based at least in part on a code block group configuration forthe first and second codewords, wherein a number of bits of the set offeedback bits correspond to a number of code blocks for a single layertransmission; and transmit a message comprising the set of feedback bitsbased at least in part on a result of the decoding operation and thedetermined association.
 26. The apparatus of claim 25, wherein the codeblock group configuration comprises: instructions executable to assignthe first and second pluralities of code blocks to code block groupsaccording to time-frequency resource boundaries for the first and secondcodewords.
 27. The apparatus of claim 26, wherein the instructions arefurther executable to: bundle respective code block groups of the firstand second codewords; and associate each feedback bit of the set offeedback bits with a respective bundled code block group.
 28. Anapparatus for wireless communication, comprising: a processor; memory inelectronic communication with the processor; and instructions stored inthe memory and operable, when executed by the processor, to cause theapparatus to: transmit, in a first transmission, a first codeword over afirst set of layers and a second codeword over a second set of layers,the first codeword comprising a first plurality of code blocks and thesecond codeword comprising a second plurality of code blocks; receive amessage comprising a set of feedback bits for the first codeword and thesecond codeword, the set of feedback bits associated with the first andsecond pluralities of code blocks based at least in part on a code blockgroup configuration for the first and second codewords, wherein a numberof bits of the set of feedback bits correspond to a number of codeblocks for a single layer transmission; and determine whether toretransmit a code block of the first or second pluralities of codeblocks based at least in part on the set of feedback bits.
 29. Theapparatus of claim 28, wherein the code block group configurationcomprises: instructions executable to assign the first and secondpluralities of code blocks to code block groups according to timeresource boundaries for the first and second codewords.
 30. Theapparatus of claim 29, wherein the instructions are further executableto: bundle respective code block groups of the first and secondcodewords; and associate each feedback bit of the set of feedback bitswith a respective bundled code block group.